collectConfidence.m

function [conf RT] = collectConfidence(window,p)

curWindow = window;
center = [p.mx p.my];
keys = [KbName('LeftArrow') KbName('RightArrow');];

%% Initialise VAS scale
VASwidth=p.stim.VASwidth_inPixels;
VASheight=p.stim.VASheight_inPixels;
VASoffset=p.stim.VASoffset_inPixels;
arrowwidth=p.stim.arrowWidth_inPixels;
arrowheight=arrowwidth*2;

% Collect rating
start_time = GetSecs;
secs = start_time;
max_x = center(1) + VASwidth/2;
min_x = center(1) - VASwidth/2;
range_x = max_x - min_x;
xpos = center(1) + 0.12.*((rand.*VASwidth)-VASwidth/2);
while (secs - start_time) < p.times.confDuration_inSecs;
    WaitSecs(.01);
    [keyIsDown,response_time,keyCode] = KbCheck;
    secs = GetSecs;
    if sum(keyCode)==1
        direction = find(keyCode(keys));
        
        if direction == 1
            xpos = xpos - 8;
        elseif direction == 2
            xpos = xpos + 8;
        end
        
        if xpos > max_x
            xpos = max_x;
        elseif xpos < min_x
            xpos = min_x;
        end
    end
    
    % Draw line
    Screen('DrawLine',curWindow,[255 255 255],center(1)-VASwidth/2,center(2)+VASoffset,center(1)+VASwidth/2,center(2)+VASoffset);
    % Draw left major tick
    Screen('DrawLine',curWindow,[255 255 255],center(1)-VASwidth/2,center(2)+VASoffset+20,center(1)-VASwidth/2,center(2)+VASoffset);
    % Draw right major tick
    Screen('DrawLine',curWindow,[255 255 255],center(1)+VASwidth/2,center(2)+VASoffset+20,center(1)+VASwidth/2,center(2)+VASoffset);
    
    % % Draw minor ticks
    tickMark = center(1) + linspace(-VASwidth/2,VASwidth/2,6);
    Screen('TextSize', curWindow, 24);
    tickLabels = {'1','2','3','4','5','6'};
    for tick = 1:length(tickLabels)
        Screen('DrawLine',curWindow,[255 255 255],tickMark(tick),center(2)+VASoffset+10,tickMark(tick),center(2)+VASoffset);
        DrawFormattedText(curWindow,tickLabels{tick},tickMark(tick)-10,center(2)+VASoffset-30,[255 255 255]);
    end
    
    % Draw confidence text
    DrawFormattedText(curWindow,'Confidence?','center',center(2)+VASoffset+75,[255 255 255]);
    
    % Update arrow
    arrowPoints = [([-0.5 0 0.5]'.*arrowwidth)+xpos ([1 0 1]'.*arrowheight)+center(2)+VASoffset];
    Screen('FillPoly',curWindow,[255 255 255],arrowPoints);
    Screen('Flip', curWindow);
end

conf = ((xpos-center(1))./range_x.*5)+3.5;
RT = secs - start_time;

%% Show confirmation arrow

% Draw line
Screen('DrawLine',curWindow,[255 255 255],center(1)-VASwidth/2,center(2)+VASoffset,center(1)+VASwidth/2,center(2)+VASoffset);
% Draw left major tick
Screen('DrawLine',curWindow,[255 255 255],center(1)-VASwidth/2,center(2)+VASoffset+20,center(1)-VASwidth/2,center(2)+VASoffset);
% Draw right major tick
Screen('DrawLine',curWindow,[255 255 255],center(1)+VASwidth/2,center(2)+VASoffset+20,center(1)+VASwidth/2,center(2)+VASoffset);

% % Draw minor ticks
tickMark = center(1) + linspace(-VASwidth/2,VASwidth/2,6);
tickLabels = {'1','2','3','4','5','6'};
for tick = 1:length(tickLabels)
    Screen('DrawLine',curWindow,[255 255 255],tickMark(tick),center(2)+VASoffset+10,tickMark(tick),center(2)+VASoffset);
    DrawFormattedText(curWindow,tickLabels{tick},tickMark(tick)-10,center(2)+VASoffset-30,[255 255 255]);
end

% Draw confidence text
DrawFormattedText(curWindow,'Confidence?','center',center(2)+VASoffset+75,[255 255 255]);

% Show arrow
arrowPoints = [([-0.5 0 0.5]'.*arrowwidth)+xpos ([1 0 1]'.*arrowheight)+center(2)+VASoffset];
Screen('FillPoly',curWindow,[255 0 0],arrowPoints);
Screen('Flip', curWindow);
pause(p.times.confFBDuration_inSecs);